drawPoints not plotting when cap style is Qt::RoundCap

When trying to draw points, using painter->drawPoints(...), the points are not plotting when painter cap style is Qt::RoundCap. It works fine for Qt::FlatCap and Qt::SquareCap.

I noticed a similar bug report (QTBUG-6721), however in this report the opposite was true; Qt:RoundCap worked fine but Qt::FlatCap and Qt::SquareCap caused the points to not be drawn. I noticed that the bug was closed so I assume it was fixed.

code ex:
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QPen tempPen = painter->pen();
QPolygon points;

points.append(QPoint(1.0, 2.0));
points.append(QPoint(2.0, 4.0));
points.append(QPoint(3.0, 8.0));

tempPen.setWidth(3);
tempPen.setCapStyle(Qt::RoundCap);
painter->setPen(tempPen);

painter->drawPoints(points);
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This should plot 3 dots which have a rounded edge, (and it did in Qt 4.5.2), however
in Qt 4.6.2 this plots nothing.